The invention is related to the field of topology, and in particular to nodes and links of an interconnection network's topology.
Most modern parallel computers are designed with multiple “nodes,” each of which is capable of some independent action. These nodes must communicate with each other, typically over what is called an “interconnection network,” which in turn is built from a set of “links” that connect the nodes. The arrangement of links and nodes is called the network's “topology.” The design of such topologies incorporates such features as how many nodes can be connected to any one link, how is routing of messages on such networks performed, and what is the protocol used for both injecting new messages into the system, from link to link, and out of the network at the appropriate target node. Typical topologies include bus, star, tree, ring, mesh, and crossbar.
A key question for the choice of a particular topology for a system is the implementation cost as seen in its totality. This cost, typically computed as a function of the number of nodes that are interconnected, is then traded against performance metrics for communication patterns of actual traffic. Topologies are preferred that lower costs for acceptable performance for the span of node counts of relevance to the target systems.